1. Stephanie Lu, MVWG Chair Seattle City Light
MVWG Report to TSS May 2013
Stephanie Lu, MVWG Chair
Seattle City Light

2. Meetings LMTF members met informally as needed PPMDTF Mar 15, 2013
HVDCTF Mar 20, 2013
REMTF Mar 26, 2013
MVWG Mar 27-28, 2013

3. Presentation Overview
Load Modeling
System Model Validation
Generator Modeling, Testing, and Validation
Renewable Energy Modeling
HVDC Modeling
Other items: JSIS Update, NERC MOD B, RAS/Relay Modeling, WECC-0101 SAR, Program Updates
Next Meetings and Workshops

4. Load Modeling 4

5. Load Modeling – Implementation Plan Update
Studies were due to TSS by March 29th (presentation with update will be provided by Craig Quist/Rikin Shah)
Phase 1 approval now planned for August TSS meeting 5

6. Load Modeling – CMPLDW Structure
Phase 1 work:
Currently LMTF uses 0.93 pu voltage threshold at low-side sub bus (uses alwscc as default for buses lower than threshold)
The programs will add the following parameters/logic:
Min voltage for creating cmpldw record (an adjustable parameter)
Min voltage for end of feeder (used to adjust feeder impedance) (an adjustable parameter)
Feeder impedance cannot be less than 0
If feeder impedance is less than jumper threshold, it gets forced to zero
PSSE will also implement improvements to recognize that not all power electronic load is reconnected after a fault 6

7. Load Modeling – CMPLDW Structure
Phase 2 work:
An IEEE paper written on FIDVR Event Analysis, led by Richard Bravo SCE that looks at PQube monitoring is available
The model of what happens when A/C stalls is pretty good
More work on whether or not A/C would stall needs more work
Discussion on how to structure the model to create a common data model so that it can keep data that keeps getting replicated 7

8. Load Modeling – CMPLDW Data
An IEEE paper is planned to include:
John Kueck’s protection and controls for motor loads under voltage sag
John Undrill’s point on wave
Richard Bravo’s A/C research results 8

9. Load Modeling – CMPLDW Data Tools
A stand-alone load model data tool is being developed by PNNL
Outputs PSLF dyd and PSSE dyr formats, enabling both PSSE and PSLF users to perform model evaluation studies.
Load Model Data Tool (LMDT4A) is available in the Composite Load Model Folder on the TSS Base Cases website. 9

10. Load Modeling – CMPLDW Benchmarking Studies
Song Wang (PAC) presented cmpldw benchmarking studies.
Simulated phase 1 & 2 for no fault line trip and three phase line trip
Minor differences are seen between PSLF 18 and PSSE 32 10

11. System Model Validation11

12. System Model Validation
Several underfrequency events have occurred since the last meeting, but nothing significant
Dmitry sends out notices to the MVWG & JSIS mailing lists
Model validation report of July 4, 2012 event aimed for MVWG approval at the next meeting
Includes a recommendation to adjust the baseload flag for gas-turbine generators that are not a full output because some of them may respond
WECC staff will develop a Sep 8th case for model validation
Includes developing a process to facilitate development of future model validation cases based on WSM data 12

13. System Model Validation
MVWG participating in the TSS WBRTF effort
MVWG contract with GE continuing to convert WECC dyd data to an “element code” definition with WSM to provide node-breaker capabilities in PSLF
Eric Allen (NERC) provided an update on the efforts of the NERC MWG efforts:
Node-breaker modeling
List of impeding data exchange
Standardization of dynamic models (starting from WECC’s work related to WECC’s Approved Dynamics Model List). 13

14. Generator Modeling, Testing, and Model Validation14

15. Synchronous Generator, Excitation and Turbine Control Models
Power Plant Model Data Task Force
OEL Model Update
Thermal governor modeling
Hydro governor model hyg6d
Power Plant Model Validation
NERC Frequency Response Initiative 15

16. Power Plant Model Data Task Force
Reviewed the list of suspected errors identified and discussed at the PPMDTF conference call. Each item was assigned for follow up with the data owners to correct or verify the data that is suspect.
If there are additional errors suspected, continue to send them to Kent.
The error check for generator saturations factors were added
S(1.2) is to be greater than S(1.0)
S(1.2) and S(1.0) are not equal to zero

17. PPMDTF – Generator Model Testing Tool
John Undrill’s data checking tool is posted in the For Generators area in Generator Testing Program Folder
NEW - “Generator_Model_Testing.zip” is posted on the WECC website in the For Generators area
Tool is for validating generator response for generator model on a 2 bus system
There are several researchers developing tools for model calibration using disturbance data, including Georgia Tech, PNNL, Univ of Wisconsin, and Univ of Texas

18. Excitation Models – OEL
IEEE working group is proposing the OEL paper at the IEEE PES GM in July 2013
Note: not the same as PSLF OEL1 or IEEE OEL95
More discussion is needed to reconsider which model WECC will recommend to be the approved OEL model 18

19. Thermal Governor Model
Revision of the thermal governor recommendation is ongoing

20. Hydro Governor Model Hyg6d is planned for June 2013 MVWG approval
Implemented in PSLF, model being shared with PSSE and PowerWorld
Main purpose of hyg6d: appropriately model the low response of the Kaplan turbines (includes hydro-servo model)
Primarily intended for use by the Army Core of Engineers turbines
Kaplan turbines represent a very significant part of the frequency responsive capacity of WECC
With approximately 15 GW of Kaplan turbines on the Columbia River, there is a need to have this model
This improved modeling will affect FRR
Impacts damping of the system for high north to south transfers
Good calibration has been shown at McNary, John Day, other Lower Columbia units, and at Albany Falls

21. Power Plant Model Validation
Power Plant Model Validation (PPMV) version 1B using PSLF play-in function is available on the WECC website in the MVWG PPMDTF Documents site
It is encouraged to install more PMUs at power plant point of interconnections 21

22. NERC Frequency Response Initiative
NERC Interconnection Frequency Response Obligations (IFRO) test results shows WECC has 840 MW / dHz.
At 840 MW/dHz, frequency response in the Western Interconnection is sufficient
Indicates to remain above the UFLS threshold of 59.5 Hz following the loss of 2 Palo Verde units. 22

23. Renewable Energy Modeling23

24. REMTF – Implementation Plan Update
REMTF is working on model validation of the prototyped models
Will have a complete set of tests completed before deploying models
Showed good validation for type 3 and type 4 wind models, some tweaks were made during this model development process between users and vendors
More work is continuing, and the plan is still to follow the approved implementation plan and timeline

25. REMTF – Other Activities
Reconciliation of NERC MOD Standards and WECC generator data and model validation policy
Model documentation and application guidelines
WECC model specifications (already approved)
Model application guide with default data for model users
Guidelines/examples for model validation
There are already existing modeling guidelines (wind powerflow, wind dynamics, PV powerflow) that will be updated. PV dynamics modeling guidelines will be developed.
Workshop focused on renewables in Fall 2013 (November)
Guideline for short circuit contribution modeling (needs to collaborate with Relay Working Group)

26. REMTF – Other Activities
Inventory of wind/PV deployment in WECC and how much is modeled in the WECC base cases

27. REMTF – Request for Data and Model Validation Tool
Requesting for participation in two ways:
Members to work with the models in the development stage
Members to provide actual data for model validation for wind (especially type 3 and 4) and solar projects
EPRI WTGMV tool is publicly available:

28. HVDC Modeling

29. HVDC Modeling Conventional point-to-point HVDC
Powerflow model: already exists, documentation is being improved
Dynamic model: being developed, a benchmark test case was developed
Siemens is to better define the rectifier and inverter models
PSLF user-written model is to be compared against Siemens implementation
ABB will review and comment on results
Manitoba Hydro may provide PSCAD model for further benchmarking.

30. HVDC Modeling VSC point-to-point HVDC
Powerflow model: specs have been agreed upon
Implemented in PSSE, beta in PowerWorld, PSLF is implementing
Next step is to benchmark across programs
Dynamic model: two proposals are being discussed
1) Siemens proposal and 2) proposal described in draft task force document
Need to consider the emulation of DC faults and decide between a DC injection type model or voltage phase between reactance model
Additional testing is needed

31. HVDC Modeling
HVDCTF will provide an educational document for the HVDC user-defined models in WECC, including PDCI, TransBay, IPP and Blackwater
Trans Bay DC model still needs to be validated
PDCI Modeling
Sylmar model still needs to be validated
Celilo is expected to be replaced in 2016, the updated model is in progress

32. Other Items 32

33. Other Items JSIS Update NERC MOD B Standard Process Update
MSRATF Update - RAS/Relay Modeling
WECC-0101 SAR Generator Validation
PSSE, PSLF, and PowerWorld provided program updates

34. Other Items – JSIS Update
NERC restarted work on PRC on dynamic monitoring equipment
BPA is performing system tests
Every other Wednesday starting March 20th
Three full tests including the Chief Joseph brake insertion in April, June, and September
This will provide good data for validating power plant models
Will provide JSIS survey of synchro-phasor projects by utilities that implemented PMUs
Paper with justification for medium sized utilities to install PMUs is in progress

35. Other Items – JSIS Update
Power plant model validation with two consultants showed different results  PMU data is a good way to get additional data to validate models
Most common model issues:
PSS (most commonly gain)
turbine control mode of operation / governor model
generator inertia
deficiencies in model structure
Other common model issues: AGC, UEL.
Through “clinical” experience, digital systems tend to stay accurate over time, and electromechanical systems tend to drift

36. Other Items – NERC MOD B
NERC is starting an informal development process for 3 MOD efforts
MOD A: ATC/TTC/CBM (MOD-001, 004, 028, 029, 030)
MOD B: Modeling Data (MOD-010 to 015)
MOD C: Demand Data (MOD-016 to 021)
MOD B proposed approach is to consolidate MOD-010 through 015 into one standard for steady-state, dynamics, and short circuit data
Considering MVWG comment to include baseline testing and validation as part of MOD B

38. Other Items – MSRATF
Reviewed MVWG model specifications process and MSRATF’s scope of work
Dmitry reviewed event-based RAS modeling
Functional description and specifications for the MATL RAS was presented
Dmitry provided a system impact study on relay modeling
Recommendation includes using "zlinw" in monitoring mode as an interim approach for power swing and FIDVR-type events as a screening tool
Model specifications for overcurrent relays by MSRATF’s Relay subgroup is expected at the next meeting

39. Other Items – WECC-0101 SAR
MVWG was requested to perform a technical study for WECC-0101 SAR on Generator Validation Policy
Questions raised:
What is the relationship between WECC Generating Unit Model Validation Policy and NERC MOD Standards?
Do we need WECC Policy since NERC Standards are passed?
What are reliability implications of reclassifying WECC Generating Unit Model Validation Policy as a Guideline?
Draft response and recommendations are under review by MVWG
Due to WSC by June 1, 2013

40. Other Items – WECC-0101 SAR
Some of the most important differences between the Policy and MOD 26/27 are:
The Policy contains a generator baseline testing requirement, whereas the MOD 26/27 standards do not. Baseline testing is critical for initial model development.
The Policy specifies a model re-validation period of 5 years, whereas the MOD 26/27 standards specify a re-validation period of 10 years.
The Policy applies to plants 20 MVA or larger and units 10 MVA or larger, whereas the MOD26/27 standards would apply to plants or units 75 MVA or larger.
The Policy has specific technical guidance for generator testing and validation, whereas the MOD 26/27 standards do not.

41. Next Meetings / Workshops41

42. 2013 Meetings Meeting Dates and Locations for M&VWG and REMTF:
June in Salt Lake City, hosted by WECC
November 4-6 in Phoenix, hosted by APS
HVDCTF, PPMDTF, and LMTF will meet independently from the main M&VWG meeting, as needed.

43. Upcoming Workshops Joint Workshop
July SRWG Workshop (2 half days)
July MVWG Workshop (2 half days)
Note: Coordinated with SRWG July Meeting
Wind/Solar Modeling Workshop Fall 2013
Generator Testing Workshop TBD